汉译英：她对该计划的成功起了重要作用。 正是汤姆做的演讲。

She has played a very important role in the success of the plan.

It's Tom who made the speech.

She played an important role in the success of the plan.

It is Tom who gave the lecture.(强调句)

she played an important role in the success of the plan.
its the very speech Tom made.

She to this plan success vital role. Is precisely lecture which Tom does.

2楼