1) I often ask him what to do and can say that his advice (be) always good and sensible.

I often ask him what to do and can say that his advice (be) always good and sensible. - I often ask him what to do and can say that his advice is always good and sensible.Глагол \"be\" употребляется в данном случае в Present Simple, так как характеризует очевидный факт в настоящем.