[ 1] A typhoon is a mature tropical cyclone which develops in the northwestern Pacific basin, in the northern hemisphere. In Vietnam, typhoons occur frequently. The [ 2] majority of such storms form from June to November. On average, they happen about [ 3] 3-4 times a year. [ 4] The hardest-hit regions are the northeast and north-central coast. Typhoons often start with [ 5] a pouring rain accompanies with accompanied by gales. They cause a large amount of terrible destruction, such as widespread flooding, flooded areas, mudslides, or proverty and property damage. They also make kill hundreds of people, die and make a large number homeless. To help people in these areas, volunteers come here go there and provide them food, drink, clean water, medical supplies, [ 6] and clothes.
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[ 1]: “typhoon” is a countable noun, so it needs an article.
[ 2]: “major” is an adjective. You need the noun form there.
[ 3]: No space between the dashes.
[ 4]: Note the hyphenation.
[ 5]: No “a”.
[ 6]: We always use “and” or “or” before the last item in a list.
