外研版（2019）高中英语必修三Unit 4同步练习

If you're a cycling lover, you will have to pay a lot of attention to your bicycle and maintain it well, for bicycle parts are exposed to wear and tear (磨损) over time and you have to examine the bicycle to see if there are any signs of wearing such as scratches, dents (凹陷) etc. Sometimes, a part may not work because it has exceeded its life expectancy. Sometimes, you will need to find replacement parts for it to keep up the performance of the bicycle.

Different parts of a bicycle will wear at different rates so it is very important that you have a basic understanding about the role played by each part. One of the most important parts of the bicycle is the frame, You will need to choose a frame that lasts for a very long time. Of course, you will see some paint scratches after some time. When you're selecting a frame, you have to think about the material. Aluminium (铝) frames will not rust easily, but they have a higher chance to dent. Steel frames will be hard to dent, but you will need to make sure they get a good paint job so that they won't rust.

Wheels also experience a lot of wear and tear and you should go for a professional seller when you want to buy wheels. There are different types of wheels that you can buy, like Zipp wheels that provide more aerodynamic efficiency (空气动力学效能). Investing in new tyres instead of going for used is a good idea because you will be able to get more use out of it. The same goes for chain as there's a higher chance of a used chain breaking. You may also experience shifting problems. However, some parts of bicycles such as pedals can be used for a long time and you can find different styles.

Other parts that you can buy used are seats, handlebars and the stem. When you are buying handlebars, you have to see if there are any dents or if they have been bent out of shape. There shouldn't be any cracks in the seat post or the handlebars. There are many shops where you can buy parts, so you will have to check the references to see how customers respond to them before you buy anything.

Lots of people find it hard to get up in the morning and put the blame on the alarm clock. In fact, the key to easy morning wake-up lies in resting your body clock Here's how to make one.

In order to make a change, you need to decide why it's important. Do you want to get up in time to have breakfast with your family, get in some exercise, or just be better prepared for your day? Once you are clear about your reasons, tell your family or roommates about the change you want to make.

Rethink mornings.

Now that you know why you want to wake up, consider re-arranging your morning activities. If you want time to have breakfast with your family, save some time the night before by setting out clothes, shoes, and bags. That's a quarter-hour more you could be sleeping if you bought a coffee maker with a timer.

Keep your sleep/wake schedule on weekends.

If you're tired out by Friday night, sleeping in on Saturday could sound wonderful. But compensating on the weekends actually feeds into your sleepiness the following week, a recent study found.

Keep a record and evaluate it weekly.

Keep track of your efforts and write down how you feel. After you've tried a new method for a week, take a look at your record. If not, take another look at other methods you could try.

A. Get a sleep specialist.

B. Find the right motivation.

C. A better plan for sleep can help.

D. And consider setting a second alarm.

E. If the steps you take are working, keep it up.

F. Stick to your set bedtime and wake-up time, no matter the day.

G. Reconsider the 15 minutes you spend in line at the café to get coffee.

I'm sure many of you are familiar with the New Year's resolution (决心) —"get fit" After a Christmas of staying 1, watching television and eating far too much chocolate, I decided enough was enough. January was going to be 2. January was going to be the start of the new, healthy me—less chocolate, more exercise, an all-round healthier lifestyle. But 3 was I going to do this? As I browsed the Internet looking for 4, I realized just how little I knew about ways to get fit. In terms of exercise, I had always 5 you either played a team sport like 6 or went to the gym. And with the arrival of January snow, playing football outside didn't seem like the best choice, and as I have a deep-rooted 7of falling off running machines, the gym wasn't going to work out either. Plus, I've never quite understood the idea of 8 to run inside when you could run outside with no monthly fee! 

9, I knew that I needed to research my choices further. The first thing I found was the world of YouTube exercise videos. There are videos for just about everything. The good thing about YouTube videos is that they are free, they are 10 at any time (you can do them whenever you want) and you don't have to leave your nice warm house to do them. But 11 you do them with a friend, it's 12 to encourage yourself to keep going, and without an instructor there with you, it's sometimes hard to know if you're doing the move 13.

I then researched local fitness classes and found my small town to be absolutely swimming with opportunity! I quickly signed up to the overall sports club, had a look at the weekly timetable and 14 to try them all out. So far I have tried out most of them. My 15 ones are by far the dance-based ones that take place to music, because it makes exercise so much more fun!

A load of food and water the disaster area.

Stick to your principles,.