Final answer:
Some sentences provided are grammatically correct, such as sentence 3 and 4, while others like sentence 2 require modifications to fix the conditional tense structure. Knowledge of proper verb forms, punctuation, and word choice is essential.
Step-by-step explanation:
The grammatical correctness of sentences can be a complex topic as it involves a range of rules and nuances. In the provided sentences, several of them are grammatically correct while others require modifications to ensure they follow standard English grammar rules. For example, sentence 3, "Follow my lead and you will be fine," is a correct imperative sentence followed by a future prediction. Sentence 4, "Are the neighbors planning to mow their grass?" is a well-constructed interrogative sentence. On the other hand, sentence 2, "If Manny were to cross the street right now, he will see us," mixes conditional tenses and should be "he would see us" to maintain the conditional structure.
Understanding correct verb forms, such as those outlined in the review question about verb selection, is essential for constructing grammatically correct sentences. Similarly, correct usage of commas, apostrophes, and homophones, as addressed in the practice review questions, is also vital for clear and professional writing.