Analysis the function of v-ing and to-infinitive in the sentences.

1） To say is one thing, to do is another. 2） His wish is to become an engineer in the future. 3） The wall needs to be repaired. 4） Finding work is difficult these days. 5） Don’t be angry with me for not having written. 6） What disappointing news! 7） Not having received a letter from his parents, he decieded to write again. 8） I often hear him singing this song. 9） The news he told me just now is surprising! 10）The teacher told the student not to be late again. 11）To cathch the first bus ,we got up at 5 a.m. 12）The building to be built next year will be the tallest in this city.