几道英语翻译题求英语高手来

1.China has been in great changes ever since the opening to the outside world in the eighties.

2.Jack has been looking after his father during his illness.
3.For students,it is the key to study hard not to waste time.
4.The efforts made by the manager to improve the working environment is very effective.
5.Their house damaged a lot in the last earthquake.
6.They has prepared adequate money for their children's education.
7.Enough attention should be paid to this problem.

尽己所能，有误请指正。

1. China has experienced great changes ever since China opened its door in the eighty
2.During his father's ill, JACK has been in taking care of him。
3. To students, the key to study hard is not a waste of time。
4. The efforts of the manager ‘s improving the working environment are very effective
5. Their house in the last earthquake was badly damaged
6. They adequated enough money for the children's education
7. The problem should be paid enough attention to