她在咖啡里加了些糖来让它更甜。

She ___sweetened her coffee by adding some sugar.

他们通过提高工资来增加这份工作的吸引力，以吸引更多员工。

They ___sweetened the offer by increasing the salary to attract more employees.

她通过添加照片使演示文稿更加吸引人。

She ___sweetened the presentation by adding photos.