he doesn't pay tariff till now 他到目前还没有支付关税,语法翻译的正确吗

English problem
Describe a specific tariff,an ad valorem tariff,and a compound tariff.What are the advantages and disadvantages of each?
不是解释这句意思 是回答这个问题 属于 The International Economy 的

英语翻译
Tariff peaks hit hard
Average tariffs faced by developing countries may be low,but "tariff peaks" that are substantially higher than the average are applied for a number of the commodities they export,such as sugar and horticultural products.For each commodity group,the developed countries have more tariff peaks and higher average peak tariffs than the developing countries.According to the WTO,the highest tariff peaks on agricultural imports in developed countries are as high as 350 percent for tobacco,277 percent for chocolate,171 percent for oilseeds,and 134 percent for poultry.
According to FAO estimates,if tariffs were reduced by 40-60 percent in developed countries and 25-40 percent in developing countries,with tariff peaks being subjected to the biggest cuts,agricultural exports of LDCs could increase by as much as 18 percent..

gmat：lift tariff到底是提高还是降低关税啊
gmat里面有一道题：kernland imposes a high tariff on the export of unprocessed cashew nuts in order
to ensure that the nuts are sold to domestic processing plants.==〉if the tariff
were lifted and unprocessed cashews were sold at world market prices,more
farmers could profit by growing cashews.however,since all the processing
plants are in urban areas,removing the tariff would seriously hamper the
***’s effort to reduce urban unemployment over the next five years.
这里箭头处明明是降低关税的意思啊,所以这个词到底是什么意思呢?

翻译across the international phone lines in tariff-free email packets

英语翻译
Tariffs and Non Tariff Barriers have a very considerable influence on the pattern of world trade.Developed countries have traditionally maintained low tariffs on primary products and much higher tariffs on semi-manufactured and manufactured goods.This tariff structure holds back the growth of manufacturing industries in developing countries by reducing their export prospects.In effect,the developed countries are protecting their own manufacturing industries from international competition.A possible solution to this problem would be a worldwide lowering of tariff barriers.
急需中文翻译