4 sentences

1. 他是我们团队的业务骨干。

   tā shì wǒ​men tuán​duì de yè​wù gǔ​gàn.

   He is the backbone of our team's business operations.

   Source: Dong Chinese Dictionary

2. 上级从各部门抽调了一批骨干。

   shàng​jí cóng gè bù​mén chōu​diào le yī pī gǔ​gàn.

   Higher authorities transferred a group of key personnel from various departments.

   Source: Dong Chinese Dictionary

3. 公司选派了一批技术骨干到海外分公司工作。

   gōng​sī xuǎn​pài le yī pī jì​shù gǔ​gàn dào hǎi​wài fēn​gōng​sī gōng​zuò.

   The company has sent a group of key technical staff to work in overseas branches.

   Source: Dong Chinese Dictionary

4. 从这张X光片可以清楚地看到，他的左腿骨干部位出现了裂纹。

   cóng zhè zhāng X​guāng​piàn kě​yǐ qīng​chu de kàn​dào, tā de zuǒ​tuǐ gǔ​gàn bù​wèi chū​xiàn le liè​wén.

   From this X-ray, it is clearly visible that there is a crack in the shaft of his left leg bone.

   Source: Dong Chinese Dictionary