It is six months         the online class started.

that

until

before

since

考查固定句型。句意：在线课程已经开始六个月了。A. that 那，那个；B. until直到..... 为止；C. before在.....之前；D. since自.....以来。分析句子可知，句中涉及固定句型“ It is +一段时间+since引导的时间状语从句”，意为“自从......以来已经有多长时间了”，since从句中用非延续性动词。故选D项。

It was the typhoon           was called Tiange           hit Zhuhai and Macao.

which; that

what; which

that; who

that; which

考查定语从句和强调句型。句意：袭击珠海和**的是“天阁”的台风。此处typhoon是先行词，指物在后面的定语从句中做主语，所以第一空填which/that；第二空是强调句句型，It is/was+强调部分+that（指人也用who）+其他，这里typhoon指物。所以第二空填that。故选A项。

With a lot of difficult problems           ,he feels like a cat on  hot bricks.

to settle

being settled

settling

settled

考查非谓语动词。句意： 因为有一大堆难题要解决，他感觉像像热锅上的蚂蚁。本句with +名词+to do sth,动词不定式表示的动作尚未发生或当时看来尚未发生。本句表示“因为有一大堆难题要解决”。故选A项。

There are 24 solar terms in a year. Grain Rain often starts in Apirl,the           month of the year.

Third

fourth

fifth

sixth

考查数词。句意：一年有24个节气。谷雨通常在一年中的四月开始。空格前有定冠词the,与可数名词单数month，要用序数词。根据

Grain Rain often starts in Apirl，可知四月份是一年之中的第四个月，要用序数词fourth。故选B项。

She reading

She reads

To read

Reading

考查时态以及省略。句意：—Joan正在做什么？—在房间里看报纸。根据句意说明描述的是现在正在发生的事情，所以使用进行时的时态，是对what is Joan doing?的回答。回答完整应该是she is reading...，此处省略了she is，故D正确。

A study shows the students who are engaged in after-school  activities are happier than        who are not.

ones

those

these

them

考查代词。句意：一项研究表明，参加课外活动的学生比不参加课外活动的学生更开心。空格处代词与the students是对应关系，可以用the ones 或者those替代。“them”指代前面提到的复数名词，不能与the students形成对应关系，“these”一般不用定语从句修饰。故选B项。

I would really appreciate       if you can make time in your schedules to attend my lecture today.

that

it

this

one

考查形式宾语。句意：如果你今天能从日程安排中抽出时间来听我的讲座的话，我将不胜感激。I would appreciate it if/when...如果/当...时，我将非常感激。it 做形式宾语。故选B项。