在商店买东西时一般用I will take it,而不是用I will buy it.陈述买什么东西了的时候只能用buy,比如I bought a pen yesterday.

buy的用法例句：

1.Somehow, he'd managed to persuade Kay to buy one for him.

不知用了什么方法，他成功说服凯给他买了一个。

2.I might buy one for a friend's birthday as a giggle.

我可能会买一件送给朋友当生日礼物，逗他开心。

3.Who wants to buy a computer from a failing company?

谁愿意从一家要倒闭的公司买计算机呢?

4.Show me which one you like and I'll buy it for you.

指给我看你喜欢哪个，我给你买。

5.You can buy a formulation containing royal jelly, pollen and vitamin C.

可以买一种含蜂王浆、花粉和维生素C的配方产品。

6.They used to buy ten kilos of beef in one lump.

他们过去常买10公斤重的整块牛肉。

7.Ford had the bright idea of paying workers enough to buy cars.

福特公司想出了一绝妙的主意：付给工人足够的薪水去购买汽车。

8.They had to buy everything at inflated prices at the ranch store.

他们不得不在农场商店以高价购买所有东西。

9.Shopkeepers buy them in bulk and resell them for £150 each.

店主们先大量购进，然后再以150英镑的单价将它们转卖出去。

10.Although people sometimes buy property sight unseen, it'sa remarkably bad idea.

尽管人们有时没看房就买了房，但这真是一个很糟糕的主意。