有一种观点认为，“自由不在于幻想中摆脱自然规律而独立，而在于认识这些规律，从而能够有计划地使自然规律为一定的目的服务”。还有一种观点认为，“‘自由’，倒过来就是‘由自’，因此，‘自由’等于‘由自’，‘由自’就是随心所欲”。这两种关于自由的观点

1946年5月4日，中共中央发出《关于清算、减租及土地问题的指示》(史称《五四指示》)，决定将党在抗日战争时期实行的减租减息政策改变为

When a spacecraft travels, one of the major problems is reentry into the Earth ’s _______.

John _______ to be a polite man. But in fact he is veryrude.

This river forms a natural _______ between China and Korea.

We can not trust him any more because he often________ his duty.

She is already 16years old. But she _______as if she were still a little girl.

In order to increase our output, we need to import more production _______.

The engineers in this lab spent several weeks _______their plans for the new bicycle.

We are _______ at the rapid progress Mark has made in this semester.