French vocabulary needed!

Start a sentence about what?

Any topic, for example "it occurs to me that" and "based on the opinion of experts" etc

I'd say you want to use the subjunctive tense around 3 or 4 times (2 or 3 different verbs) in your writing piece, so find sentence starters that lead in to the subjunctive. Do you know what this is?

Yes although it is not the level of french that we are learning at the minute - i was simply hoping for a list of high-level vocabulary to use in lessons and assessments that would boost my grade - thanks for the tip though i will be sure to remember that for when i can cope with subjunctive!

It would be better to learn the words for 'based' or 'occur' than to simply memorise the sentence. There are far too many for me to name, but I'll give you a couple:

J'estime que- another variant of je pense que/je crois que
Il me semble que- It seems to me that..
Ce qu'on doit.. What we must.. (then add a verb like remember, realise, do)

Any topic, for example "it occurs to me that" and "based on the opinion of experts" etc

Il me semble que.... It seems to me that

Il parait que... It appears that

Les savants/ sages disent que...the learned/ wise say that

Selon les spécialistes.. According to the experts.

Listening to French music while looking at the lyrics translated to English is a massive help.

En fait, on ne met pas le cédille à "merci". (Actually, we don't put any cedilla in "merci")
D'une autre part, tu peux commencer des phrases avec: (Otherwise, you could start some sentences with)
"Il paraît évident que..." (It seems obvious that...)
"Selon l'opinion/l'avis/la position des experts..." (Based on experts' opinion/take on the matter/position...)
"Ces documents de recherche font mention de..." (These research documents mention...)
"Les recherches actuelles suggèrent que..." (Present research suggest that...)

C'est sûr que les débuts de phrases vont varier selon le type de texte qu'il faudra que tu écrives. (Of course, the ways you start a sentence will vary depending on the type of text you're writting).
Les exemples que j'ai donnés se retrouvent davantage dans l'argumentation. (The exemples I've given you would be found mostly in argumentative texts.)

Je ne sais pas ce qu'on enseigne en GCSE, mais les organisateurs textuels m'ont toujours été utiles. (I don't know what you learn in GCSE, but I've always found transition words and phrases to be useful).
Tu peux en trouver sur ce lien: (You can find some at this link (Not translated))
http://www.ccdmd.qc.ca/media/rubri_o_55Organisateurs.pdf