2 sentences

1. 他必须在月底前补齐这笔货款的差额。

   tā bì​xū zài yuè​dǐ qián bǔ​qí zhè bǐ huò​kuǎn de chā'é.

   He must make up the balance of this payment by the end of the month.

   Source: Dong Chinese Dictionary

2. 差额选举比等额选举更能体现选民的意愿。

   chā'é xuǎn​jǔ bǐ děng'é xuǎn​jǔ gèng néng tǐ​xiàn xuǎn​mín de yì​yuàn.

   Competitive elections reflect the will of the voters better than uncontested elections.

   Source: Dong Chinese Dictionary