1. Phil was training for the marathon, so he had to abstain from junk food.
2. Natalie wanted to watch the prospective on TV.
3. The foreman ensured work at the construction site went on smoothly.
1. Phil was training for the marathon, so he had to [abstain] from junk food.
In this sentence, the word "abstain" is the correct choice. "Abstain" means to refrain or hold back from doing something, especially from indulging in certain activities or habits. In the context of the sentence, Phil is refraining from eating junk food as part of his marathon training.
2. Natalie wanted to watch the [prospective] on TV.
The correct word in this sentence is "prospective." However, it seems there might be a slight issue with the usage of the word. "Prospective" typically refers to potential or likely future events or possibilities. If you meant to convey that Natalie wanted to watch something specific on TV, you might want to consider using a different word like "program" or "show."
3. The [foreman] ensured work at the construction site went on smoothly.
In this sentence, the correct word is "foreman." A foreman is a person in charge of a group of workers, especially in a construction or industrial setting. The sentence is stating that the foreman is responsible for ensuring that the work at the construction site progresses smoothly.