The man showed us such a heavy stone ________ no one could lift it.
A．that B．as C．which D．and
The number of the audience，________ we had expected，was well over one thousand.
A．whom B．who C．which D．as
A lot of language learning，________ has been discovered，is happening in the first year of life，so parents should talk much to their children during that period.(2012·安徽，29)
A．as B．it C．which D．this
The air quality in the city，________ is shown in the report，has improved over the past two months.(2012·福建，23)
A．that B．it C．as D．what
(2013·北京，26)—What do you think of teaching，Bob?
—I find it fun and challenging.It is a job ________ you are doing something serious but interesting.
A．where B．which C．when D．that
(2013·福建，24)It's helpful to put children in a situation ________ they can see themselves differently.
A．that B．when C．which D．where
