English grammar rules
Universal truths are always in simple present tense.
The present perfect tense is used to express a recently completed action.
Future tense is not used in time clause.
“For” shows a period of time up to now.
“Since” shows some point of time in the past.
Nouns like news, physics, mathematics, measles are plural in form but they are treated as singular.
Nouns like government, audience, company, staff, media, crew are used with both plural and singular verbs.
Little is used to emphasize there is a small amount of something.
Much emphasizes a larger amount.
When we think about members as individuals we use “each”.
When we make a general statement for all the individuals we use “every”.
“AN” is used before nouns which begin with a vowel sound (a,e,i,o,u).The initial sound, not the spelling is important.
The following words have vowel sounds so we use “an” before them:
an MP, an hour, an umbrella.