You need to have the perfect form.

必须要用成式。

Please make a sentence using the present perfect tense.

请以成式的时态造句。

Present perfect is about an experience which happened from a time in the past until now.

成式是关于从过去到的经历。

Americans also tend to use the simple past tense while Britons use the present perfect.

不过美国人依倾向于用一般过去式，而英国人依会用成式。

American and British English speakers use the present perfect verb tense in similar ways.

英式英语和美式英语成式的使用上是比较相似的。

When I have a class, I'll usually do a few lessons on past perfect before moving on.

当我上课的时候，我通常会先上几节关于过去成式的课，后再继续习。

At a certain age, we've aII had reIationships...

我们各自拥有 不太美的过去成式。

Now we have a filtration type of lab that you can do literally at home.

而，我们有了一种可以家里成的过滤式检测方法。

British English speakers would generally use the present perfect in this situation, as in " I've lost my phone… again" .

这种情况下，说英式英语的人一般会用成式" I’ve lost my phone… again" 。

You can even write present progressive or present perfect progressive in our comments.

您甚至可以我们的评论中写下进行式或成进行式。

So we should be able to get to a South Korea-type prioritized testing thing within a few weeks.

所以我们应该能够几周内成韩国式的优先测试。

So, this could also be called present perfect progressive. And this one can also be called past perfect progressive.

所以，这也可以称为成进行时。而这个也可以称为过去成时进行式。

Well, first of all you probably realize these are all present perfect progressive sentences, and they have a lot of things in common.

好吧， 首先可能意识到这些都是成的进行式句子，它们有很多共同点。

So, if you feel that you need some more practice, by all means, watch that individual class on the past simple, on the past perfect, okay?

所以，如果觉得需要更多的练习， 一定要看那个简单的过去式， 过去成式的个人课程，好吗？