become的过去式和过去分词形式是什么

He became very weak towards the end of his life.

他临终时很虚弱。

What became of that student who used to live with you?

以前和你住在一起的.那个学生后来怎么样了？

It soon became apparent that no one was going to come.

很快就很清楚，没人会来。

In the 1990s the area became a magnet for new investment.

这个地区在20世纪90年代成了新的投资热点。

She only became coherent again two hours after the attack.

她发病两小时之后才恢复了清楚地说话的能力。