Restoring the Missing Words in a Welding Procedure
You are a welding trainee at a ship repair yard in Limassol. Your instructor has given you page 2 of the company's welding procedure specification (WPS) for manual metal arc welding of 8 mm mild steel plate, but the file was converted from a scanned document and eight words dropped out. The instruction is: one word from the box for each gap; a word may be used once, more than once, or not at all; the finished page must be grammatically correct and must make technical sense.
Word box: before / be / otherwise / until / must / which / for / if / although / being / will
The instructor stresses one point: a WPS is audited by a classification society surveyor, so a gap filled with a weak modal verb where the company rule is mandatory is not a small mistake - the procedure will be rejected and the welders will be working to a document that does not exist.
1. Fill gaps (1)–(8) and justify each choice in one line. '(1) ___ welding begins, the welder must check that the plate edges are clean and dry. Any rust, oil or paint within 25 mm of the joint must (2) ___ removed, (3) ___ porosity may result. Welding must not start (4) ___ the preheat temperature of 100 °C has been reached. Each pass (5) ___ be cleaned with a wire brush (6) ___ is clean and dry. Electrodes must be dried in the oven (7) ___ at least one hour. The interpass temperature must not exceed 250 °C; (8) ___ it does, welding must stop.'
Read the worked answer
(1) Before - a time clause opening the sentence; 'Before welding begins' sets the condition for everything that follows. (2) be - passive form after the modal: 'must be removed'. The word 'removed' is already there, so the missing auxiliary is 'be'. (3) otherwise - the clause states the consequence of not removing the contaminants; 'otherwise' means 'if that is not done'. 'Although' would signal a contrast that does not exist, and 'if' would need a full clause ('if they are not removed'). (4) until - the start of welding is prohibited up to the moment the temperature is reached; 'until' marks that boundary. (5) must - a company requirement, not advice. 'Should' is grammatically possible but, as the instructor says, a WPS that merely advises is not a procedure; the correct modal is the mandatory one. (6) which - a defining relative clause about the brush. Note that 'that' would also be correct, but 'that' is not in the box. (7) for - duration: 'for at least one hour'. (8) if - a real condition: the case in which the temperature exceeds 250 °C.
Unused: although, being, will.
2. Explain why gap (3) must be 'otherwise' and not 'although' or 'if'. Then rewrite the sentence containing gap (4) so that it begins 'The preheat temperature …' and keeps exactly the same meaning.
Read the worked answer
Why 'otherwise'. The two clauses are linked by consequence, not by contrast or by a simple condition:
- Contaminants remain → porosity results. 'Otherwise' carries the meaning 'if the removal is not carried out'. It works because the preceding clause is an instruction, and the second clause is what happens when the instruction is ignored.
- 'although' would make the second clause a concession - 'porosity may result, even though…' - which is the opposite of the intended warning.
- 'if' cannot simply be inserted: 'if porosity may result' reverses the logic (it would make porosity the condition rather than the consequence), and there is no subject and verb available after the gap.
Rewriting the gap-(4) sentence. Original: 'Welding must not start until the preheat temperature of 100 °C has been reached.'
Rewrite: 'The preheat temperature of 100 °C must be reached before welding starts.'
Meaning is preserved: both sentences prohibit welding before the same temperature is achieved. What changes is the focus - the original forbids the action, the rewrite makes the temperature the subject and the obligation. Both are acceptable in a WPS; the second reads better when the temperature is the parameter being audited.