Answer:
1. If <em>I had not hurt my ankle,</em> I wouldn't have stopped running.
2. If only my friends <em>liked to play</em> team sports.
3. <em>I wish I hadn't bought</em> a car.
4. If <em>only I hadn't dropped</em> my fishing rod in the river.
5. James wishes <em>he could take part</em> in the competition.
Explanation:
<u>The subjunctive mood is used to talk about imaginary or impossible situations, and to express regret.</u> Sentence one makes use of Third Conditional, which is formed with the Past Perfect and would have + past participle. Finally, <em>I wish</em> and <em>if only</em> are used with the Past Simple to refer to an unlikely situation in the present, while the Past Perfect indicates regret over something that has already occurred.
