Make one sentence from two. use who/that/which. 1) a bus goes to the airport. it runs every half an hour 2) some people were arrested. they have been released now. 3)a waitress served us. she was impolite and impatient.

1) A bus wich runs every half an hour goes to the airport. (which употребляется с неодуш.)
2) Some people who were arrested have been released now. (who употребляется с одушевленными
3)A waitress that served us was impolite and impatient. (официантка, которая = that)