He was puzzled by this phenomenon. He began to try every approach _________ the best way of working it out.
Kate was very fond of speaking French, ______ indeed she spoke well.
Mary is the only one of the girls who ________ in for sports.
Is this museum ______ the students visited last year?
They got to the railway station, _______ the train ________.
Lincoln had very little free time ______ he could spend studying then.