(A)Those travelers (B)are completing their trip (C)on Delta should report to (D)Gate three. 

The first ______ appeared during the last period of the dinosaurs’ reign.

At around two years of age, (A)many children regularly produce (B)sentences (C)contain three or four (D)words.

The car (A)listed (B)in the advertisement had (C)already (D)stalling.