There are too many of us.

The world is overpopulated. There are too many of us. The humanity will die out from hunger and diseases. / Мир перенаселен. Нас слишком много. Человечество вымрет от голода и болезней.

I've thought a lot about this.

I've thought a lot about this the past few days. / Я много об этом думал последние несколько дней.

He is full of shit.

You seem to know a lot about this stuff.

You seem to know a lot about this stuff. Have you been on a date before? / Похоже, ты много об этом знаешь. Ты раньше был на свидании?

I've given it much thought.

There are just so many of them.

He had many enemies.

I did a lot of thinking.

You sure know a lot about his.

This means a lot to me.