Spouse visa - original vs copies

I'm confused as to whether I need to send in all original documents or some or all can be copies (other than the passport) in terms of the supporting documents for a spousal visa. Can someone help please?...

Also, for the English proficiency, it says "they must provide the original academic qualification certificate (provisional academic qualification certificates are not acceptable)" - what does "original academic qualification certificate" mean? A diploma? It seems odd that I would need to send in an original diploma....

Thank you!

I'm confused as to whether I need to send in all original documents or some or all can be copies (other than the passport) in terms of the supporting documents for a spousal visa. Can someone help please?...

Every document MUST be original, and then you also have to send copies of everything you want to be returned to you - they may keep the originals if you don't send copies.

When it comes to things like bank statements, they must either be official statements printed by the bank, or if you print them from the internet, they must be either stamped and signed by the bank on every page, or accompanied by a letter from the bank confirming their authenticity.

See Appendix FM-SE for details about the document formats required:
https://www.gov.uk/guidance/immigration-rules/immigration-rules-appendix-fm-se-family-members-specified-evidence

Also, for the English proficiency, it says "they must provide the original academic qualification certificate (provisional academic qualification certificates are not acceptable)" - what does "original academic qualification certificate" mean? A diploma? It seems odd that I would need to send in an original diploma....

Appendix FM-SE (linked above) tells you exactly what format the document must be in:

31. Evidence of an academic qualification (recognised by UK NARIC to be equivalent to the standard of a Bachelor’s or Master’s degree or PhD in the UK) and was taught in English must be either:

    (a) A certificate issued by the relevant institution confirming the award of the academic qualification showing:
        (i) the applicant’s name;
        (ii) the title of award;
        (iii) the date of award;
        (iv) the name of the awarding institution; and,
        (v) that the qualification was taught in English Or,
    (b) If the applicant is awaiting graduation or no longer has the certificate and cannot get a new one, the evidence must be:
        (i) an original academic reference from the institution awarding the academic qualification that;
            (1) is on official letter headed paper;
            (2) shows the applicant’s name;
            (3) shows the title of award;
            (4) confirms that the qualification was taught in English;
            (5) explains when the academic qualification has been, or will be awarded; and
            (6) states either the date that the certificate will be issued (if the applicant has not yet graduated) or confirms that the institution is unable to re-issue the original certificate of award. or
        (ii) an original academic transcript that
            (1) is on official letter headed paper
            (2) shows the applicant’s name;
            (3) the name of the academic institution;
            (4) the course title;
            (5) confirms that the qualification was taught in English; and,
            (6) provides confirmation of the award.

32. If the qualification was taken in one of the following countries, it will be assumed for the purpose of paragraph 31 that it was taught in English: Antigua and Barbuda, Australia, the Bahamas, Barbados, Belize, Dominica, Grenada, Guyana, Ireland, Jamaica, New Zealand, St Kitts and Nevis, St Lucia, St Vincent and the Grenadines, Trinidad and Tobago, the UK, the USA.

Yes, they want the actual diploma.  It's weird.