“九曲黄河万里沙”，黄河水中大量泥沙主要来源于[ ]

A．青藏高原          

B．内蒙古高原

C．华北平原          

D．黄土高原

根据汉语提示完成句子，每空词数不限。

1. My father has worked in the factory ______________ (一辈子).

2. The doctor told the patient to eat ____  (少) rich food and do ____  (多) exerase.

3. Lucy is ____ (最大的) of the five sisters.

4. Thanks to our parents, all the children ____________(过着幸福的生活) .

5. The children should never work because of the conditions of work not suitable ____________(对年轻人来说).

6. My grandparents ________(成长) in those days.