1. I find it difficult to master French.
2. I find it difficult mastering French.
3. The heavy snow made it difficult to walk on the street.
4. The heavy snow made it difficult walking on the street.
5. He believed it difficult to go abroad to study.
6. He believed it difficult going abroad to study.
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Can we use the gerund instead of the to-infinitive?
All are OK. Using the infinitive is much better, but using the gerund in casual speech is OK.
Yes, we can use both the gerund and the infinitive form after certain verbs or expressions, such as "find it," "make it," and "believe it." However, there is a slight difference in meaning between the two forms.
1. "I find it difficult to master French." In this sentence, the preposition "to" is used before the infinitive form "master," indicating the purpose or goal of finding it difficult. The focus is on the action of mastering French as a whole.
2. "I find it difficult mastering French." In this sentence, the gerund form "mastering" is used. This suggests that the difficulty is ongoing and continuous. The focus is more on the process of mastering French rather than the overall goal.
3. "The heavy snow made it difficult to walk on the street." Here, the preposition "to" is used before the infinitive form "walk," indicating the purpose or activity that is difficult. The sentence emphasizes the difficulty of walking on the street.
4. "The heavy snow made it difficult walking on the street." Using the gerund form "walking" here implies that the difficulty of walking is continuous and ongoing. The focus is on the act of walking rather than the specific situation.
5. "He believed it difficult to go abroad to study." In this sentence, the preposition "to" is used before the infinitive form "go," indicating the purpose or goal of going abroad to study. It emphasizes the difficulty of going abroad.
6. "He believed it difficult going abroad to study." In this sentence, the gerund form "going" is used. This suggests that the difficulty of going abroad for studying is continuous and ongoing. The focus is on the act of going rather than the specific situation.
So, while both forms are grammatically correct, they convey slightly different meanings. The infinitive form emphasizes the goal or purpose, while the gerund form emphasizes the ongoing nature of the action or activity.