Kindly tell the proper use of verb here

[new2grammar]

our quality expert minutely supervise / supervises the quality level of our diamonds

our quality experts supervise / supervises the quality level of our diamonds

 

[jayan12]

our quality expert minutely supervise / supervises the quality level of our diamonds

our quality experts supervise / supervises the quality level of our diamonds

Not a teacher.

I would choose supervises for the first sentence and supervise for the second one.

 

[kannanvv07]

Again not a teacher
1. Supervises
2. Supervise

 

[new2grammar]

Our stringent quality policy helps us in upholding our credibility in the market.

Kindly tell its help or helps...our is plural I suupose

 

[sarat_106]

Our stringent quality policy helps us in upholding our credibility in the market.

Kindly tell its help or helps...our is plural I suupose

The underlined expression is a noun phrase pre-modified by words highlighted with the singular noun 'policy' as its head and it is the subject of the sentence which needs a singular verb(helps). Our is a possessive adjective modifying the noun policy.