Nested Paratactic Extension vs Nested Hypotactic Enhancement With Ellipsis

He used coloured chalk whenever it was available and whenever it helped. 

He used coloured chalk	whenever it was available	and whenever it helped
α	x β
	1	+ 2

He used coloured chalk sporadically and whenever it helped.

He used coloured chalk sporadically	and he used coloured chalk	whenever it helped
1	2
	α	x β

Characterisation As Happening

How are you doing?

From above, this is a demand for specific information: a characterisation of the self; a congruent realisation of the meaning would be how are you?.  So, from above, this clause is attributive relational.

how	are	you	doing
circumstantial Attribute: quality	Process:	Carrier	attributive

From roundabout, the lexical choice of the verb, and from below, the 'present in present' tense, both locate the clause more materially: as construing an ongoing happening.

how	are	you	doing
Manner: quality	Process:	Actor	material

The clause then realises a characterisation as an ongoing happening, thereby providing both of the complementary perspectives on change: the inert stability of 'being' and the active change of 'doing-&-happening'; see Halliday & Matthiessen (1999: 136, 159-65).

Condition Marked By Subject–Finite Inversion

were	concerns about the health of global trade	to become	more elevated
Finite	Subject	Predicator	Complement
Mood		Residue
Process:	Carrier	attributive	Attribute
interpersonal	topical
Theme: unmarked		Rheme

The subjunctive MODE of the verb marks the irrealis of the condition.