aim at

1. 瞄准

He aimed at the bird but missed.

他瞄准那只鸟射击, 可是没打中。

2. 以……为目的

What are you aiming at?

你的用意何在?

aim for

1. 瞄准

I was aiming for the tree.

我瞄准了那棵树。

2. 致力于

We'll aim for quality.

我们将力求提高质量。