You need to have the perfect form.

必须要用完。

Please make a sentence using the present perfect tense.

请以现在完时态造句。

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

现在完是关于从过去到现在经历。

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，而英国人依会用现在完。

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

英英语和美英语在现在完使用上是比较相似。

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

当我上课时候，我通常会先上几节关于过去完课，后再继续学习。

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

我们各自拥有 不太完美过去完。

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

而现在，我们有了一种可以在家里完过滤检测方法。

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

在这种情况下，说英英语人一般会用现在完" I’ve lost my phone… again" 。

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

您甚至可以在我们评论中写下现在进行或现在完进行。

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

所以我们应该能够在几周内完韩国优先测试。

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

所以，这也可以称为现在完进行时。而这个也可以称为过去完时进行。

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， 首先你可能意识到这些都是现在完进行句子，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，如果你觉得你需要更多练习， 一定要看那个简单过去， 过去完个人课程，好吗？