You need to have the perfect form.

必须要用完成式。

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

英式英语和美式英语在在完成式的使用上是比较相似的。

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

而在，我们有了一种以在家里完成的过滤式检测方法。

Please make a sentence using the present perfect tense.

请以在完成式的时态造句。

Sonia, can you help us explain this phrase more?

Greg 说，我已经完成大概一半了。 I've gotten about half of it done。句主词加 has 或 have gotten something done 是在完成式。 have gotten 表示已经使得怎样，而片语 get something done 是做了某件事。 来看例句。

So is the world made for introverts or extroverts?

今天的 usage tip 是介绍 it 加 has been 加过去分词 加 that 的句 它用於间接引述 以许主词 it 作为开头 搭配在完成式的被动语态 表达一直以来都有 that 子句所述的主张 常用於本句的动词 大多具有声称或是揭露的含义 除了 argue 以外呢 此句以使用 claimreveal， report 等字词使用被动语态淡化消息来源并将重点放在所主张的内容上来看例句It has been revealed that several celebrities were involved in the scandal据透露有多位名人卷入这起丑闻？

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

在完成式是关于从过去到在的经历。

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

不过美国人依然倾向于用一般过去式，而英国人依然会用在完成式。

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完成式的课，然后再继续学习。

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，说英式英语的人一般会用在完成式" I’ve lost my phone… again" 。

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

您甚至以在我们的评论中写下在进行式或在完成进行式。

We're looking here, and we look at the present perfect.

我们看这里, 我们看在完成式。

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

我们各自拥有 不太完美的过去完成式。

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

所以我们应该能够在几周内完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，这以称为在完成进行时。而这个以称为过去完成时进行式。

The simple past and the - sorry, the present perfect.

简单过去式和 - - 对不起, 在完成式。

Follow NPR's coverage of President Trump trying to do things no other president has on Trump's terms from NPR.

关注NPR对特朗普总统试图以特朗普式方式完成前所未有之举的报道，来源NPR。

Now, let's look at the present perfect.

在, 让我们来看看在完成式。

Present perfect, also, past participles, we can remember that.

在完成式, 还有过去分词, 我们以记住。

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， 首先你能意识到这些都是在完成的进行式句子，它们有很多共同点。