Help Plse

[kamanu15]

Friday. 19A switch on incubator for built-up area (11)
23A A first class average recalled cause of weakness (7) Is it anaemia?
16D very secular revolutionary party (6)
13A saw amateur team doctor coming back (5)

[aelmpvw]

19a conurbation

[aelmpvw]

16d social

[aelmpvw]

13a axiom

[johnny.5]

19 a
conurbation
anagram

[johnny.5]

23 looks correct

[dannyk13]

19a.Conurbation - anagram of on incubator
23a.Anaemia- a + ai (first class) & mean(average) reversed
16d.Social - so(very) + laic(secular) reversed
12a.Axiom - A (amateur) + xi(team) + mo(doctor) reversed