The phrase "a third plank" is correct and usable in written English.
It can be used when referring to an additional component or element in a series, often in discussions about plans, policies, or proposals.
Example: "In addition to the first two proposals, we need to consider a third plank that addresses environmental concerns."
Alternatives: "an additional component" or "a third element".
So this must be a third plank of an effective anti-AIDS strategy.Condoms.Condoms
When you're comfortable at that level — that is, not feeling a lot of muscle soreness — add a third plank.
But the bill omits a third plank of the FCC's 2015 net neutrality rules: The ban on "paid prioritization," or the ability of Internet providers to speed up certain websites in exchange for money.
Adopting a third plank of the Conservative programme, Mr Darling announced that from 2009 air taxes would be levied on the flight, rather than the passenger, a measure that is regarded as better targeted at cutting carbon emissions.
Police then launched a third plank to look at computer hacking and misuse of data.
The southernmost portion of Route 287 was the location of a third plank road, this time beginning at the mouth of Larrys Creek in the eponymous community to the current day location of English Center.
Stick with that for a few days, then add a second plank.
A second plank of the race science case goes like this: human bodies continued to evolve, at least until recently – with different groups developing different skin colours, predispositions to certain diseases, and things such as lactose tolerance.
If this is the case, you will need to cut a second plank to fill in the rest of the space: To do this, you can either cut two planks into even pieces, so that their combined width covers the thread, or you can use a full plank and cut a smaller strip to fill in the extra space.
This third plank requires a cultural shift for public, patients and particularly professionals.
There was also talk of a common eurozone deposit guarantee scheme, the third plank in the banking union scheme, safeguarding people's savings anywhere in the single currency area.
