1. 确实：surely 的确地 | sureness 确实 | surety 保证

2. 稳健：携手 hand-to-hand grip | 稳健 sureness | 撑竿式跳 pole vaule jump

3. 的确的,稳妥的：intruder 闯入者 | sureness 的确的,稳妥的 | yardstick 尺码

4. 稳健准确：坚持下去 play away stick to , hold on | 稳健准确 sureness | 以智取胜 out-think ; out-wit

noun

1. the quality of being steady and unfailing

e.g. sureness of hand

2. freedom from doubt
belief in yourself and your abilities

e.g. his assurance in his superiority did not make him popular
after that failure he lost his confidence
she spoke with authority

Synonym: assuranceself-assuranceconfidenceself-confidenceauthority