题目

When a group of people meet for a conference, or training course, there is always a feeling of uncertainty and discomfort. (25)______ ______ people know each other, they feel uncomfortable in the new strange situation, because it is different. Games and team building activities can relax people. Teams unite and work together when they identify (26)______ they think serves a common purpose. Activities and games break down the barriers, and therefore help develop close relationships. Everyone is different. Taking part in new games and activities outside of the work situation (27)________台式电脑使用一段时间后，为保证电脑的稳定性，需要打开主机箱盖除尘，这是因为散热风扇的扇叶在转动过程中与空气摩擦带上了　    　，可以　    　轻小物体，所以灰尘会附着在扇叶上．