B. Rewrite each of the following sentences, using the construction with the pronoun,
followed by the verb, followed by an infinitive:
1. Walking in the morning is good for health.
2. Crossing the large river would be very difficult.
3. Achieving all is not possible.
4. Skiing down the mountain was exciting.
5. Doing exercises necessary for body building.
6. Visiting America was a wonderful experience.