1 . 阅读短文，根据短文内容填空。在未给提示词的空白处仅填写1个适当的单词，在给出提示词的空白处用括号内所给词的正确形式填空。
Over the past few years, the Chinese market of mobile payment 1 (witness) a booming development. With the emergency of the mobile internet, smartphone shopping has 2 (gradual) become trendy, especially with the 18 to 30-year-olds 3 make up the lion’s share in the mobile payment market. Since it is so convenient to pay with a smartphone while shopping, many consumers prefer 4 (pay) by their phone rather than by cash or credit card.
