4 sentences

1. 磁铁同性相斥，异性相吸。

   cí​tiě tóng​xìng xiāng​chì, yì​xìng xiāng xī.

   Like poles of a magnet repel each other, while opposite poles attract.

   Source: Dong Chinese Dictionary

2. 物理学中，异性电荷相互吸引。

   wù​lǐ​xué zhōng, yì​xìng diàn​hè xiāng​hù xī​yǐn.

   In physics, opposite charges attract each other.

   Source: Dong Chinese Dictionary

3. 他在异性面前总是感到很拘束。

   tā zài yì​xìng miàn​qián zǒng​shì gǎn​dào hěn jū​shù.

   He always feels very self-conscious in front of the opposite sex.

   Source: Dong Chinese Dictionary

4. 他最近桃花很旺，吸引了不少异性。

   tā zuì​jìn táo​huā hěn wàng, xī​yǐn le bù​shǎo yì​xìng.

   He's been very lucky in love lately, attracting many members of the opposite sex.

   Source: Dong Chinese Dictionary