题目

The building project________next year is not easy________in time. A．being carried out，to complete B．carried out，to be completed C．to be carried out, to complete D．to be carried out, to be completed   答案：Cto be carried out为不定式短语作定语，表明先行词承受该动作且是一个将要发生的动作；第二个空为sth. be easy to do 结构。  某半导体激光器发射波长为1.5×10-6m，功率为5.0×10-3W的连续激光。已知可见光波长的数量级为10-7m，普朗克常量h＝6.63×10-34J·s，该激光器发出的 (A)是紫外线 (B)是红外线 (C)光子能量约为1.3×10-18J (D)光子数约为每秒3.8×1016个