“Difficult to hit?” is also a sentence fragment in English.  Clipped if you prefer, which may be why Okrand rendered it as he did.  
 
Another example:
 

  Dochvetlh DIlmeH Huch 'ar DaneH

  How much do you want for that?  (TKD)

--Voragh

On Behalf Of SuStel

On 8/3/2017 10:53 AM, mayqel qunenoS wrote:

Can we have a {-meH} phrase followed by question ?
e.g.:
 
maQapmeH chay' mavangnIS ?
In order to succeed how do we need to act ?
 
romuluSngan DaHoHmeH, nuq 'oH nuH'e' ?
romuluSngan DaHoHmeH, nuH 'oH nuq'e' ?
In order that you kill the romulan what is the weapon ?
 
choQaHmeH bIHeQQo''a' ?
in order to make me angry you refuse to comply ?

I don't see any problem with this.

I can only think of one canonical example of -meH on a question, and it's a lousy example. qIpmeH Qatlh'a' difficult to hit? (ST5) It's a bad example because it's talking about being difficult for the purpose of hitting, which is not really the purpose of being difficult.

-- 
SuStel
http://trimboli.name