求一些英文的列式,要列出算式来.只要正确立即满意.比如：（five greater than an unknown nu

求一些英文的列式,要列出算式来.只要正确立即满意.比如：（five greater than an unknown number)=5n
（four more than an un-known number） （six less an unknown number) (twice an unknown number.) (an unknown number diminished by eight) (six plus an unknown number) (an unknown number diminished by seven) (eight less an unknown number)