A couple of years ago I was on a mini bus on Vietnam's Cat Ba Island, a popular tourist spot near Ha Long Bay. I got talking to the woman next to me. "What you do?"

"I'm a journalist... ah, nha bao," I said. "What about you?"

"I am English teach," she replied.

She taught in a primary school and said this was one of her first times speaking with a foreigner. English is mandatory in primary schools in Vietnam, though people begin learning at different ages in different parts of the country. All students have to learn it, but unless they receive extra tuition—or are exceptionally talented—few can speak it fluently.

State news recently reported that in Hanoi only 18% of primary school teachers can pass the exams the government sets. In other parts of Vietnam it is not much higher. They must receive a mark of 6 or higher on the International English Language Testing System, an international standard for test, or the equivalent. A score of 6 to 6.5 is what most universities require their foreign students to achieve. Though not at the standard of a native speaker (who should rate a 9 to 9.9) it is still high enough that many university students spend many hours and much money at private English-teaching centres—usually staffed by foreigners—to achieve this score. Expecting countryside primary school teachers to do the same seems optimistic, at least.

The Ministry of Education does not plan to sack teachers first time they fail, but will give them till the next academic year to improve. A second fail would earn the sack. One Ho Chi Minh City-based official estimated that to get all primary school teachers up to standard will take until 2020. A main reason, one teacher told the Vietnam News, is that most teachers, especially in rural areas, almost never have a chance to speak and listen in live practice.

The few successful ones must be unusually motivated. A friend of mine, who teaches at a private secondary school, told me that though she'd been taught English from Grade 6, most of what she knew came from her own study. She'd pick up English language newspapers each week and try to listen to the radio or television. She thinks the main problems facing primary school teachers who've already failed the test once might be the time and resources to study and pass. “They'll need the money to pay for intense courses. I don't think the government give much support.”

It's not just the education sector but also sometimes the educated. I once worked as a sub-editor at a local newspaper. My job was to fix the grammar and English of the translators as well as more standard copy-editing. This meant detangling various clauses that had tripped over themselves twice in the same sentence (our grammar differs rather a lot). There was also the odd over-literal translation to figure out. What was a "multiple somersault train"?, I once wondered. A roller-coaster.