Obviously a lot of thought has gone into the plan.

"You seem to have given this a lot of thought."

She had clearly given this a lot of thought and so was ready with her answer.

You can tell a lot of thought went into this one.

It is not something to which I have given a lot of thought.

I put a lot of thought and research into them.

Sorry, I'm sure a lot of work and thought has gone into the new design.

They have given it a lot of thought, and taken on board what people think.

So, I mean, a lot of thought was given to this.

I want you to know I've given this a lot of thought.