We will be losing money this year unless that new economic plan of yours well[ ]

Why don’t we go out for a walk The weather is fine and pleasant.— Let’s go.

In the past few years, research has suggested that Vitamin D may increase the level of serotonin（血清素）, one of the key nurotransmitters influencing our mood, and ________it helps to relieve mood disorders.

The teacher told us that light ______ faster than sound

Simon usually plays_______ guitar on Sunday morningand plays_______ chess on Sunday afternoon.