根据中文提示，用词组的适当形式填空 。
（1）Hurry up!We are (等候)you at the gate．
（2）He was so tired that he (入睡)as soon as he lay down．
（3）Michael is (擅长)physics but he is weak in chemistry．
（4）Li Lei seldom goes to school (步行)．He usually takes a bus there·
（5）A lot of trees were (砍伐)．As a result，there were more sandstorms．
