can you help me translate the following sentences?

Grammar could be mastered more easily flexiblely when understood in the context of sentence or the whole passage. for instance, we all know that a plural form of a countable noun should be put after the word "many", nevertheless, students might sometimes come across such a sentence:"Many a student has seen this painting" .（许多同学都见过这幅画）。In this sentence, single form of a countable noun is arranged following "many", with its predicate also implying the single form, both of which conspire to indicate a plural usage; Another example is that a subjunctive structure is generally put after "suggest",yet some student may also have read the following sentence: "The look on his face suggested that he was scared." (他脸上的表情表明他吓坏了。) simply because "suggest" means"表明、使人认为" when thing(s) rather than people as its subjective.

什么意思